Shell-Type Reactor with Radial Baffles

ABSTRACT

The object of the present utility model is to cope with the problems of large volume of the presently known cellpacking type of reactor and the poor effect of heat transfer, and to provide a shell-type reactor with radial baffle, which transfers heat well and reduce the volume of the reactor, comprising a shell ( 1 ) and an internal cold plate assembly ( 2 ), said internal cold plate assembly ( 2 ) fixed within said shell( 1 ); wherein a gas radial distribution vessel ( 9 ) and a radial gas cylinder ( 10 ) fixed within said shell ( 1 ); said radial distribution vessel ( 9 ) and said radial gas cylinder ( 10 ) could counterchange according to the difference of the gas flow direction; several circles of radial baffling assemblies ( 12 ) are provided between said radial distribution vessel ( 9 ) and said radial gas cylinder ( 10 ), said radial baffling assemblies ( 12 ) consisting of several baffling components fixed in an interval mode, an axial baffling through groove or hole is provided between the adjacent baffling components. The present utility model has advantages of the great effect of heat transfer, the simple structure, the small overall size.

CROSS REFERENCE TO RELATED PATENT APPLICATION

This patent application claims the priority of the Chinese patentapplication No. 200620077859.3 with a filing date of Sep. 27, 2006.

FIELD OF THE INVENTION

The present utility model relates to a shell-type reactor, especiallyrelates to a lamella reactor with the baffling cold plate employed in agas-solid catalytic reaction bed to transfer heat, and specificallyrelates to a shell-type reactor with radial baffles.

BACKGROUND OF THE INVENTION

FIG. 1 shows the presently known catalytic reactor with fixed bed. Inthis catalytic reactor, the heat transfer of the chemical heat releasedis carried out by the heat transfer element with the cooling tubes, andthe coolant is usually cool reacting gas. But the catalyst bed out ofthe tubes usually employs an axial flow bed layer, the majordisadvantages of this reactor are as follow:

(1) The gas cooling tubes have the characteristic with poor efficiencyof heat transfer and finite quantity of heat transfer, and thetemperature distribution of the catalyst bed layer is not perfect.

(2) The axial-flow resistance is great and the production capacity isrestricted.

To intensify the heat transfer capacity of the reactor and improve thetemperature distribution of the catalyst bed layer, the cellpacking typeof the water cooling reactor (Referring to FIG. 2) is developedzealously in the last 20 years. And obtain some favorable effect, butstill many obvious disadvantages are as follow:

(1) The resistance (of the catalyst) in the tubes is so great that itneed to increase the number of the tubes and the diameter of thereactor.

(2) The reactors require the better material nature and the thick tubeplate with a major diameter, and the manufacture hardness is too great.So it costs much.

(3) The utilization ratio of the catalyst loaded in the reactors is poorand the diameter of catalyst loaded in the reactors is large, and itbadly limits the large-scale level of the uniserial production capacity.For example, when the industrial scale increases to the 200,000 ton, thediameter of the reactors for the production of methanol is about 4 m,and the ratio of its high-diameter is always 1-2.5. And it alsoincreases the hardness of its transportation and its fixing.

According to these disadvantages, it develops the cellpacking type ofthe water-cooling reactor with radial flow in these years to solve theproblem of the large resistance (FIG. 3 and 4). Finally, the reactorresistance is reduced from 0.5 MP to 0.1 MPa, and the ratio of thehigh-diameter is also increased to 3-8.

Although the cellpacking type of reactor with radial flow solves theproblem of resistance, it also causes other problems as follow:

(1) The low resistance of the radial flow causes the oversize ventsection, the short flow path, and the extraordinary smallness of thevelocity of flow. And it causes the coefficient of heat supplied in thecatalyst side out of tubes excessively low, which is only ⅕- 1/20 of thenormal value of the axial flow. So the heat transfer efficiency fallsdown, the quantity of heat is hard to carry away, and part of thecatalyst is easy to overheat.

(2) Employing the thick tube plate with a major diameter cannot get ridof the disadvantages of the high cost and the large manufacturehardness.

(3) The loading and unloading of catalyst is difficult.

(4) Because of the low heat transfer efficiency, it requires morecooling tubes. So the availability ratio of the high pressure space iseven lower than that of the cellpacking type of the reactor with axialflow.

SUMMARY OF THE INVENTION

The object of the present utility model is to cope with the problems ofthe large volume of the presently known cellpacking type of reactor andthe poor effect of heat transfer, and to provide a shell-type reactorwith radial baffles, which transfers heat well and reduces the volume ofthe reactor.

The technical program of the present utility model is as follow:

A shell-type reactor with radial baffles, comprising a shell 1 and aninternal cold plate assembly 2, said internal cold plate assembly 2fixed within said shell 1; wherein a gas radial distribution vessel 9and a radial gas cylinder 10 fixed within said shell 1; said radialdistribution vessel 9 and said radial gas cylinder 10 may counterchangeaccording to the difference of the gas flow direction; several circlesof radial baffling assemblies 12 are provided between said radialdistribution vessel 9 and said radial gas cylinder 10, said radialbaffling assemblies 12 consisting of several baffling components fixedin an interval mode, an axial baffling through groove or hole isprovided between the adjacent baffling components.

Said baffling components employ the structure of hollow cold plates;said baffling components employ the structure of hollow cavity, or thestructure of cold plates which are full of water or other coolant.

Said baffling components employ the structure consisting of the solidfixed plates and the axial array tubes which are inseparate from saidsolid fixed plates, or the structure consisting of the solid fixedplates and the tubes which are separate from said solid fixed plates,while the solid fixed plate guides reacting gas through the axialbaffling through groove or hole in order to prevent the reacting gasfrom passing through the adjacent pipes

The section of said radial baffling assemblies 12 employs a circle-arcstructure, a polygonal line structure or a cylindrical structure.

Radial through holes fixing on said radial distribution vessel 9 andsaid radial gas cylinder 10. Said radial through holes are stagger withsaid axial baffling through groove or said through hole.

Said axial baffling through groove or said through hole 16 is oppositeto the central region of the baffling component in its neighboringcircle.

The advantages of the present utility model are as follow:

(1) The present utility model employs the plate cooling element insteadof the tube-type water cooling element, and develops the reactor fromthe presently known cellpacking type to the lamella type. With the sameheat transfer surface, the space which the plate cooling element occupysis less than that of tube-type cooling element. So the spaceavailability ratio of the board shell-type reactor is greater than thatof cellpacking type reactor, and it may usually increase 5-15%.

(2) In the present utility model, baffle can increase the supplying heatcoefficient of the gaseous phase effectively.

In all of the catalytic bed with the radial flow cold plate or the cooltube before the present utility model, although it has the advantage ofthe minimizing resistance by employing the oversize section of radialflow passage, the short flow passage and the low velocities, it leads tothe low supplying heat coefficient of the gaseous phase even lower than200 kcal/m².c.h. So the poor heat-transfer intensity of this type ofreactor cannot be solved well. In the present utility model, iteffectively increases the supplying heat coefficient as high as 500-2000kcal/m².c.h, by masterly arranging cold plate for the baffling flow,reducing the aeration section and increasing the length of the passage.

(3) The present utility model can effectively improve the heat-transfercharacteristic of the catalytic bed. The gas flow rate in the radialcatalytic bed changes along with the direction of radius, which meansthat the gas flow rate reduces when R increases. And the heat-transfercoefficient which relates to the gas flow rate also reduces when Rincreases, but the reaction heat increases along with the R'sincreasing. So the heat transfer and the exothermic character of thetype of pure radial reactor cannot be synchronizing. The present utilitymodel overcomes this disadvantage. Employing the design with bafflingflowing can make the flow rate of any passage equal and divide each unitlength of the catalyst quantity equal, so it can effectively overcomethe disadvantage of the presently known radial catalytic beds. Inaddition, the baffling cold plate of the present utility model can alsobe designed as the nonequideistant structure, to make the area of theunit cold plate in the different reaction process and the heat-transferquantity which changes along with the reaction realizes completenesssynchronizing and then achieve the real optimization.

(4) The present utility model employs the novelty structure combiningthe radial flow distribution and the baffling cold plate. The radialflow distributor has the maximal advantage of the low fluid resistance,and it employs baffling in the catalyst bed layer. So its fluidresistance which is mostly 0.1-0.3 MPa, is between the pure radial flowresistance (Usually 0.05-0.2 MPa) and the axial flow resistance (usually0.3-0.8 MPa)

(5) The present utility model no longer employs the thick tube platewith a major diameter, so the manufacture hardness and the cost reduce.And the high-diameter ratio can be 5-8 (the high-diameter ratio of thenormal axial flow of the cellpacking type of reactor is 2-4). So thediameter of the reactor which employs this technology is ½-¼ less thanthat of other reactor with the same production capacity, which is stillin favor of the transport and the large scale tendency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is the abridged general view of the presently known fixed bedcatalytic reactor.

FIG. 2 is the abridged general view of the presently known cellpackingtype of water cooling reactor.

FIG. 3 is the first of the abridged general views of the presently knowncellpacking type of water-cooling reactor with radial flow.

FIG. 4 is the second of the abridged general views of the presentlyknown cellpacking type of water-cooling reactor with radial flow.

FIG. 5 is the abridged general view of the present utility model.

FIG. 6 is the top view of FIG. 5.

FIG. 7 is the abridged general view of the water supply device supplyingfor cooling water in the embodiment of the present utility model.

FIG. 8 is the first one of the abridged general views of baffle in thepresent utility model

FIG. 9 is the second one of the abridged general views of baffle in thepresent utility model.

FIG. 10 is the third one of the abridged general views of baffle in thepresent utility model.

FIG. 11 is the fourth one of the abridged general views of baffle in thepresent utility model.

FIG. 12 is the fifth one of the abridged general views of baffle in thepresent utility model.

DETAIL DESCRIPTION OF THE INVENTION

The present utility model is further described by combining with thedrawings and the embodiments.

Refer to FIG. 5.

A gasses shell-type reactor with radial baffles, mostly consists of aninternal cold plate assembly 2, a header 3, the soft water inlet tube 4,a gas inlet 5, a gas outlet 6, a catalyst self-discharge opening 7, aninert filler 8, a gas radial distribution vessel 9, a radial gascylinder 10, the catalyst 11, the radial baffling assemblies 12, a tailtube 13, a vapor outlet tube 14 and a manhole 15. Referring to FIG. 5,the manhole 15 is located on the top of shell 1, the internal cold plateassembly 2 is fixed in the shell 1, the gas radial distribution vessel 9is fixed in the shell 1, the radial gas cylinder 10 is fixed in thecenter of the gas radial distribution vessel 9, the radial gas cylinder10 is connected with the gas outlet 6, the gas inlet 5 is connected tothe cavity which is located between of the shell 1 and the gas radialdistribution vessel 9. The inert filler 8 is fixed in the lower part ofthe internal cold plate assembly 2, and the catalyst self-dischargeopening 7 which extends out of the shell 1 is connected to the lowerpart of the internal cold plate assembly 2. Several circles of radialbaffling assemblies 12 which provide an axial baffling through groove orhole are fixed between the radial distribution vessel 9 and the radialgas cylinder 10. Referring to FIG. 8-10, the section of the radialbaffling assemblies 12 employ a circle-arc structure, a polygonal linestructure or a cylindrical structure. Each circle of radial bafflingassemblies 12 consists of several baffling components fixed in aninterval mode (The specific number can be determined after the relevantcalculation as it is required). The axial baffling through groove orhole is provided between the adjacent baffling components. The bafflingcomponents employ the structure of hollow cold plates (Referring to FIG.6 and 8-10), or the structure consisting of the solid fixed plates 17and the axial array tubes 18 which are inseparate from said solid fixedplates (Referring to FIG. 11), or the structure consisting of the solidfixed plates 17 and the tubes 18 which are separate from said solidfixed plates (Referring to FIG. 12). Both ends of the hollow watercooling plate (Referring to FIG. 5) are connected to the header 3 by therelevant tail tube 13. And the lower header 3 is connected to the sourceof cooling water by the soft water inlet tube 4, the upper header 3 isconnected to the air chamber through the vapor outlet tube 14. Thecatalyst 11 is loaded between the radial distribution vessel 9 and theradial gas cylinder 10.

According to the need, the structure of water cooling plate may bedesigned as a circle-arc structure, a polygonal line structure or acylindrical structure (Referring to FIG. 8-10), and it may be designedas the structure consisting of the solid fixed plates 17 and the axialarray tubes 18 which are inseparate from said solid fixed plates(Referring to FIG. 11) or the structure consisting of the solid fixedplates 17 and the tubes 18 which are separate from said solid fixedplates (Referring to FIG. 12).

The theory and the structure of radial baffling assemblies 12 whichemploy the structure consisting of the solid fixed plates and the axialarray tubes connected to said solid fixed plates is similar with thewater cooling plate.

The present utility model is now detailed by combining with each of maincomponents.

The basic structure of the reactor in this embodiment mostly consists ofthe bearing shell, the internal cold plate assembly and the air chamber.

1. Shell

Shell 1 may employ unattackable chrome molybdenum steel. And itsdiameter, height and thickness are designed according to the productionscale and the operating pressure (The normal diameter is φ2000 mm-φ6000mm and the normal height is 8000 mm-25000 mm). The lower end of shell 1provides several intake pipes 4, and the catalyst is conveniently loadedfrom the top and downward through the upper manhole or the spherical topopened. Several self-discharge openings 7 are provided at the lower endof the shell 1, and the catalyst is automatically unloaded. A gas inlet5 for the feed gas and a gas outlet 6 for the reacted gas are providedin the center of the spherical bottom.

2. The Internal Cold Plate Assembly

The internal cold plate assembly 2 is used to fixing the radial bafflingassemblies 12, and the internal cold plate assembly 2 is an integralheat-transfer component which provides the radial distribution vessel 9and the radial gas cylinder 10. The coolant in the cold plate may beliquid such as water, and it also maybe gas or others. It mostly employswater as an example to describe the embodiment.

3. Heat-transfer component with water-cooling baffle. It mostlycomprises several pieces of baffling components with water flowinginside, the inlet and outlet connecting pipe, the upper and lower header3, the upper and lower eduction tube 4, 14, and so on. Because theheat-transfer medium in the cold plate is coexistent with the saturatedvapor, the water cooling plate is nearly a sort of isothermalheat-transfer body.

4. The radial baffling catalytic bed. After the feed gas which flowed inthe reactor radially flows through the radial distribution vessel 9 andinto the bed, it is guided by the hollow water-cooling bafflingcomponent which is arranged into the concentric circles, and then formsbaffling flow to repeatedly flow through the annular catalyst layer andmake the chemical reaction while transferring heat to the cold plate.Finally it is collected by the radial gas cylinder 10 and flows out(Referring to the direction of arrow in FIG. 5 and 6). Because theheat-transfer medium in the cold plate such as the saturated water holdsthe constant temperature, the saturated water is guided by the top ofreactor to the upper air chamber and produces the steam incidentally,and the rest soft water forms the automatic cycle what it flows throughthe down pipe and returns to the lower end of the cold plate (Referringto FIG. 7). So the temperature distribution of the catalyst bed layer inthe reactor is much close to the constant temperature, in order to makethe whole catalyst bed layer react at the highly stable state which isapproximately isothermal. And the temperature of the whole bed iscontrolled by the pressure of the air chamber. The arrangement andstructure of the radial baffling assemblies 12 is that arrange severallayers (Or cycles) along the circumference direction of the reactor. Oneor several hollow water cooling plates encircle and form each layer. Thecatalyst 11 is loaded between the plates. The vent opening is providedat the joint of each cold plate in the same circle, and the ventopenings of the cold plates which are located in its neighboringinternal cycle and its neighboring outer cycle is stagger with eachother, in order to form the gas of the catalyst layer to the baffling(Referring to FIG. 6). The water outlet and the water inlet are providedin the upper end and the lower end of each cold plates, which areconnected with the tubes of the header by using the curving tail tube13. The tube of the header provides a water header pipe which providesthe connection of the rising pipe and the down pipe of the air chamber.The arrangement of the water cooling plates is designed by the designeraccording to the heat output of the catalytic reaction which isdetermined by the production capacity, heat quantity transferred by thecold plates, the resistance of the bed, and so on. Finally determine theoverall size of the reactor and the arrangement of cold plates, whichcomprises the heat-transfer area of the cold plate, the number of thecold plate in each cycle, the number of the baffling flow, the spacingof the cold plate, the length of the cold plate, the size of the coldplate water passages, and so on. The section of the water cooling platemay be several types, such as the polygonal line structure (Referring toFIG. 8), the circle-arc structure (Referring to FIG. 9), the cylindricalstructure (Referring to FIG. 10), and so on. But whichever type it is,the water cooling plate forms the baffling flow. Designers choose anytype of the cold plate structures according to their analyzing of theadvantages and the disadvantages. When employing the baffling componentsin the FIG. 11 and 12, it may also employ the section equivalent to thesection in the FIG. 8-10.

The object of the radial flow distributor in this embodiment is toreduce the bed fluid resistance. The radial bed consists of thedistribution vessel and the gas cylinder, which are fixed in the inneror the outer according to the flow direction (Ento-ectad or ecto-entad).

The difference of the radial flow distributor in the present utilitymodel and the presently known radial reactor is the opening's positionof the distribution vessel and the gas cylinder. The opening's positionof the distribution vessel and the gas cylinder in the present utilitymodel is fixed in the position opposite to the centerline of the watercooling plate, in order to make the flow which flows in or out form thebaffling flow.

1. A shell-type reactor with radial baffles comprising: a shell (1) andan internal cold plate assembly (2) fixed within said shell (1); a gasradial distribution vessel (9) and a radial gas cylinder (10) fixedwithin said shell (1); said radial distribution vessel (9) and saidradial gas cylinder (10) may counterchange according to the differenceof the gas flow direction; several circles of radial baffling assembly(12) with a polygonal line structure being provided between said radialdistribution vessel (9) and said radial gas cylinder (10); said radialbaffling assembly (12) including several baffling components fixed in aninterval mode, an axial baffling through groove or hole being providedbetween the adjacent baffling components.
 2. The shell-type reactor withradial baffles of claim 1, wherein said baffling components possess astructure of hollow cold plates, or a structure of a solid fixed plateswith attached axial array tubes, or a structure of a solid fixed plateswith separated tubes.
 3. The shell-type reactor with radial baffles ofclaim 2, wherein said baffling component has hollow cavity, in which isfull of water or other coolants.
 4. The shell-type reactor with radialbaffles of claim 1, wherein plurality of radial through holes aredistributed on the surfaces of said radial distribution vessel (9) andsaid radial gas cylinder (10), said radial through holes are staggeredwith said axial baffling through groove or said axial baffling throughhole.
 5. The shell-type reactor with radial baffles of claim 1, whereinsaid axial baffling through groove or said axial baffling through hole(16) is opposite to the central region of the baffling component in itsneighboring circle.